Folded cartons or boxes are often used with a number of products which come into contact with the hands of the consumer. Particularly in pharmaceutical products, it is important to know whether or not the boxes have been opened at any time prior to sale or certain uses.
Often the prior art has turned to the use of attaching supplemental labels over fold lines and opening lines of cartons. If the labels are broken, one assumes the carton has been opened by a curious consumer or other. It is sometimes difficult or inconvenient to use labels in connection with the tucked-in end of folding cartons to determine whether or not they have been opened. Sometimes packaging machines are slowed down in their operation by the use of such labels or other complications arise. Often changes in overall manufacture may be required when supplementary labels are used.